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Welcome
Houses That Work
Energy Design Conference – Duluth, MN
February 20th, 2018
Local Sponsor
EEBA National Education Partners
Who’s here and What would you like to talk about?? 5
Today’s Agenda
■ Industry trends
■ Essential elements in a home
■ Basic building science to effectively manage Heat, Moisture and Air in buildings
■ Creating systems that work for healthy, safe durable, efficient and sustainable homes.
■ Foundation systems
■ Above grade wall systems
■ Roof systems
■ Heating, Ventilation and Air Conditioning Systems (HVAC)
■ Marketing and selling basics
6
What is our goal? 7
“Create an enclosure that separates the indoors from the outdoors...and is safe and healthy for the people inside.”
In addition to:Creating a high performance home that is; energy efficient, durable, healthy, aesthetically pleasing,
respectful to the environment and profitable...
House SystemsWhat’s Changed in that home in the last 35 years? How has this impacted the home? 8
Environment
Enclosure Mechanical
Occupants
What’s the decision tree? 9
■ Decisions made on price
■ Decision made on warranty/service issues
■ Customers satisfaction/expectations
■ Process/cycle times
■ Supplier availability
■ We are here to help reinforce your decision process
What’s Changing quicker….?Codes or expectations of consumers?
■ Comfort
■ Quiet
■ Lifestyle
■ Investment quality
■ Demographics
■ Access to information
10
1. Air Temperature(Ambient)2. Surrounding Surface
Temperature(MRT)3. Humidity
PERSONAL FACTORS:1. Air movement-Drafts(Air Speed)2. Occupant Activity AND
Sensitivity(Metabolic Rate and Clothing )
ASHRAE 55….”Mean Radiant Temperature”http://comfort.cbe.berkeley.edu/
THERMAL COMFORT DEFINED:ASHRAE 55( 40 years old)
How does the body lose (transfer) heat?
• 15% humidity/perspiration
• 35% convection/air movement
• 50% radiation heat exchange.
The Temperatures of the surrounding walls ,floors and windows impacts comfort MORE than air temperature(Thermostat).
Energy Efficiency Scale
■ Every 1 point reduction is equal to a 1% reduction in energy use
13
14Code adoption as of March, 2017
Codes respecting the science15
Codes will be more Performance Objectives 16
Defining High Performance Homes…. 17
Tight Construction
18
Improved Insulation Systems
19
Improved Insulation Systems
20
Improved Durability
21
High Performance Windows 22
Efficient Heating and Cooling Equipment
23
Effective Distribution
24
Efficient Water Heating 25
Ventilation & IAQ Systems
26
Lighting-Energy EfficiencyCompact fluorescent Bulbs 27
Appliances 28
Water Efficiency 29
Smart Technology 30
Sustainable Materials 31
Site planning 32
33Renewable Energy Systems
34
35Total U.S. and Household Energy Use
30 years ago….
Hot water 15%
Heating 75%
Lights /
Appliances
10%
IECC 2015….
SMALLER TOTAL CIRCLELOAD PROFILE HAS CHANGED
NET ZERO / ZERH….
Heating 13%
Hot Water 12.5%
Occupant /Baseload 67.5%
Air Conditioning 3%
HRV /Fans 4%Occupants /Base loads
WHERE DO WE START?….
START WITH THE LARGEST ENERGY CONSUMPTION
ACTIVITY (BTU & KWH, NOT $...)
…THE LARGEST CONTRIBUTORS TO THE ALMIGHTY SPACE HEATING LOAD
41A Complicated Business
discussing a high performance heating system installation in field
■ Extensive collection of materials
■ Uncontrolled building conditions
■ Communication challenges
■ Workforce training
■ Changing codes
■ Elevated consumer expectations
Average Annual Rainfall for Philadelphia, PA 50 inches/yr
Average Annual Rainfall for Los Angeles, CA 15 inches/yr
Average Annual Rainfall for Portland, OR 40 inches/yr
Average Annual Rainfall for Miami, FL 60 inches/yr
Average Annual Rainfal for Minneapolis, Mn 28 inches/yr
Courtesy of Building Science Corp.
Average Annual Rainfall for Seattle, WA - 40”inches/yr
Where we live affects performance.
Columbia, SC - 49 ”inches/yr
Minneapolis, MN - design conditions
Condition ASHRAE 99% / 1%
Winter, design dry bulb (F) -8°F
Summer, design dry bulb (F) 87.9°F
Summer, design wet bulb (F) 72.3°F
Degree days-heating 7565
Degree days-cooling 751
Precipitation 28
43
Our investment in the structure is significant 44
45
We often under invest in managing moisture. 80% of building failures=water related…yet less than 1% of total construction cost spent on managing water -flashings
46
47
The resulting damage can be extensive
48What defines durability?
1. Design
2. Material selection
3. Installation detail
4. Maintenance
Will they be affected by:
‣ Water
‣ Heat
‣ Radiation
‣ Insects
49
50
51
The Building Industry is Changing 52
“You must learn from the mistakes of others. You can’t possibly live
long enough to make them all yourself.”
Sam Levenson
The Building Enclosure
■ Developing a strategic approach
53
What rules must be followed?
54
Building Science Fundamentals
Heat
Air
Moisture
55
The Physics of Buildings
■ Moisture moves from more to less■ Moisture moves from warm to cold ■ Heat flows from warm to cold■ CFM (air) out equals CFM (air) in■ Heat, air & moisture are one■ Drain the rain■ Things always get wet - let them dry■ All the action happens at the surface
56
57
Methods of Heat Transfer
‣ Conduction
‣ Convection
‣ Radiation
Heat flow = Exposed Area × Temp. DifferenceR-Value
Example: With R-30 insulation in the attic
Heat Loss through 1000 sq. ft of ceiling, 70 F inside, -10 F outside
=1000 × (70 - (-10)) / 40 = 2,000 BTUs/hr
58Conduction Heat Loss/Gain
Thermal Bridging- Problem
Heat flows more easily through wood studs = Conduction
■ 2” x 6” stud = R-6
■ Insulation cavity = R-19+
60
What about...double, triple studs, rim joists, headers and partition wall
intersections?
61
■ Without insulated sheathing, a quarter of your walls are not insulated!
■ On a square house, it’s the equivalent of one whole wall!
25% of the surface Area is wood!
Thermal Bridging - Stud Loss
23% framing-no windows
R-ValueCavity Studs
Outside air film 0.17 0.17
½” OSB 0.62 0.62
2 x 6 stud-wood n/a 5.83
cavity insulation* 21 n/a
½” gypsum 0.45 0.45
Interior air film 0.68 0.68
Totals 22.92 7.75
Total wall 15.26
Effective R-value of 2 x 6 wall- no windows or doors
62
* denotes “perfect” insulation installation
63
Exterior Insulated sheathing will be normal
The dew point discussion
0
10
20
30
40
50
60
70
80
MAY JUN JUL AUG SEP OCT NOV DEC JAN FEB MAR APR
2 x 6 wall R21 w/ plywood sheathing
Temperature at cavity side of sheathing- R-20 cavity w/
plywood sheathing
Daily temperature
Dewpoint at 35% RH, 70°F
Potential for condensation
0
10
20
30
40
50
60
70
80
MAY JUN JUL AUG SEP OCT NOV DEC JAN FEB MAR APR
2 x 6 wall w/ R-10 sheathing
Temperature at cavity side of sheathing- R-20 cavity w/ R-10
ext.
Mean Daily temperature
Dewpoint at 35% RH, 70°F
Potential for condensation
69
70
Insulated Concrete Forms
Increasing use as whole house solution for walls of thermal enclosure from foundation to roof
71
73Managing radiant heat flow
74
DP 30
Air Flow...
■ Understanding pathways & pressures
75
76Reasons we want houses to be tight
■ Most cost effective energy saving measure - 20% -30% savings
■ Makes homes quieter and cleaner
■ Makes homes more “comfortable”
■ Reduces water entry - homes last longer
■ Makes homes healthier - controlled air quality
■ Environmental benefits because we are not wasting energy
77
From an Energy Perspective - We Would like Houses to be very tight
■ Indoor Air Quality
■ Moisture problems
■ Chemical pollutants
■ Combustion Safety
■ “The walls have to breathe”
Are there any concerns of Houses Being “Too Tight”?
78
Wind Pressure Stack Effect Mechanical Pressure
Graphics courtesy: Canada Mortgage and Housing Corporation
Air pressure in buildings
Stack effect - pressures created by air temp. differences 79
80
Neutral pressure plane of building
Moisture laden air flow can create problems 81
Wind effects are variable 82
Mechanical systems can also adversely affect performance 83
Moisture Flow
■ The basic principles of a complicated subject
85
Forms of Moisture 86
■ Solid
■ Snow & Ice
■ Liquid
■ Rain, soil moisture & condensed vapor
■ Gas (Vapor)
■ Evaporated moisture
Moisture Flows 87
■ Liquid Flow (gravity driven)
• Rain
■ Capillary
• Material wicking
■ Air Transport
• Air pressure induced flows of moisture laden air
■ Diffusion
• Molecular transport via vapor pressure drive (no airflow)
Moisture Flows 88
Liquid Water
Water follows gravity
■ Site
■ Foundations
■ Walls
■ Roof
89
Graphic courtesy of Building Science Corp.
Capillary Flow
■ Wood & concrete wick water
■ Water can climb (in wood) in excess of 300 ft!
■ Water can climb (in concrete) in excess of 1,000 ft!
90
Capillary91
Material type
Location
Proximity to soil
Spacing
Sealing
92Vapor Diffusion
■ Diffusion
■ Migration of moisture by means of vapor pressure differential
■ Occurs in either direction based on climate conditions and interior levels of humidity
■ One seasonGraphics Courtesy of Building Science Corp.
1/2 Pint
Vapor Diffusion is complex93
F
Air Transport of Water Vapor
■ Air Leakage• Moisture flow through
a 1in2 hole by air leakage
■ Flow quantity• 14 Pints of water in a
two week period
94
Air barriers are far more important than vapor retarders in most cases
Graphics Courtesy of Building Science Corp.
95
The Physics of Buildings
■ Moisture moves from more to less■ Moisture moves from warm to cold ■ Heat flows from warm to cold■ CFM (air) out equals CFM (air) in■ Heat, air & moisture are one■ Drain the rain■ Things always get wet - let them dry■ All the action happens at the surface
97
NOW THAT WE KNOW THE BUILDING SCIENCE BASICS....
■ We can begin to create walls, roofs and foundation systems that work
98
99
What are the key components of the structure and envelope?
Occupants
Equipment & Systems
• Framing• Insulation• Air sealing• Windows/doors• Materials• Finishes
Structure & Envelope
Let’s Review
Managing the elements100
First we need to protect our building system from water
Liquid Water - Drain Everything 101
The Six D’s:
1. Drain the site
2. Drain the building
3. Drain the assembly
4. Drain the opening
5. Drain the component
6. Drain the material
102
Graphics from EEBA Water Management Guide
Drain the Site
103
Text
The site and soil affect many decisions
Adjusting grading to redirect water away from the homes
104
Landscape too close to the foundation 105
106
Ground slopes away from the wall at 5%. (6” per 10’)
Graphics from EEBA Water Management Guide
Remember proper grading
108
Graphics from EEBA Water Management Guide
Drain the Building
Rain on cladding system
Liquid Water
Cladding is 1st line of defenceWater gets behind all types of cladding
by:Liquid
CapillaryAir pressures
109
110
Deflection
Durability
The Four “D”sKey Strategies to building
Water Management
Drainage
House wrap
Drying
111
Canada Mortgage and Housing Corporation
1. Deflection 80%
2. Drainage (1/16th”)
3. Drying (perms)
4. Durability
Resistance (treated wood? Why?)
The four D’s of wall design
113Deflection?
116
Gutters are important to any water management strategy
Graphics from EEBA Water Management Guide
117
Follow the path of water will it create a problem?
Flashing & Gutters must effectively redirect water 118
119
Concentrate on the path of flow...
120Kickout Flashing
121Drainage?
Integration of flashing systems 122
From EEBA Water Management Guide
Flashing must be integrated with the drainage plane123
124
Flashing needs backing too 125
127
128
129Inadequate pan flashing
130
131
Barrier Wall Installation has limitations
132
133
134
Drying?
135
136
Demonstrating a Method
■ The pan flashing system connects to the drainage plane
137
138Windows need special attention
Site-Constructed or manufactured pan flashings for window and door openings in frame walls
139
140
142
143
144
Use low pressure, low expanding foam around openings
145
Window Installation-Great Job!146
147
Flashing at Shed Roofs
Draining Housewraps148
Venting our Cladding
149
Air Flow assists drying
Create intentional airflowWhen using brick & stone &
siding in:Humid summer climates
Rainy climatesWood sheathing
applications
150© Building Science Press. Reprinted with permission.
151
152
Stone should have drainage and ... ventilation 153
154
Create an intentional gap between trim and flashing
155
156Holes Add Up
157
158
159
160
161
Water Managed Foundations
■ Types and design strategies
162
163When below grade....
■ Remember the rules:
■ Moisture is present
■ Insects are close by
■ Soil gas can enter
■ Surfaces can be cool
■ Concrete wicks water
■ Foundations can be very challenging
164
Foundation systems
165
Capillary break applied between footing and foundation wall
■ Required whenever one porous component meets another
■ Footing/slab to foundation wall
■ Foundation wall to framing
■ Under slabs-on grade Footing to foundation connection
166
168Membrane under-slab
169Drainage Board Application
Foundation Insulation170
Insulation - Slab Perimeter
■ Heat loss is significant - 30% - 50% - in the heating season through an un-insulated slab (FOREVER!!)
■ Slab perimeter insulation strategies (vertical, horizontal, interior, exterior)
171
See EEBA Builder’s Guide for details
Same house, same time of year, which one is right? 172
Insulating a crawl space floor is difficult and often ineffective 173
174
175Basements need thermal insulation
Insulated inside the wall
Externally Insulated
Internally Insulated
Foundation type, climate and soil conditions all affect performance
176Basement Slab Insulation
Types■ Block
■ Poured
■ ICF
■ T-bar type
■ Precast
■ Wood
177
178
Graphics Courtesy of Building Science Corp.
179
180
Graphics Courtesy of Building Science Corp.
181
Membrane over slab 182
Insulated Concrete Forms
■ An innovative and proven technology for foundations and walls
184
Insulated Concrete Forms
■ Allows for controlled drying towards the interior
■ Insulation and foundations in one system
■ Interior finished can be directly applied
■ Remember the capillary break
185
187ICF Wall
189
190
195A wall system needs to perform
■ Provide strength & rigidity
■ Be durable
■ Control light & solar gain
■ Control noise
■ Control rain penetration
■ Control air flow
■ Control heat flow
■ Control water & vapor flow
Air Barriers
196
Air Barriers
■ Air Barriers are systems of materials
■ Designed and constructed to control air flow between a conditioned space and an unconditioned space
■ Air barrier system is the primary air enclosure boundary that separates indoor (conditioned) air and outdoor (unconditioned) air
197
198
Define breaks and create a plan to manage them
Common Holes We Miss
PlumbingHVAC
ElectricalFraming Holes
SoffitsBehind Tubs
Chimney ShaftsCantilevers
199
A very helpful OC research project
Air Flow Barrier-Interior
■ Airtight Drywall Approach
■ Connecting and sealing the materials to stop air flow
■ Must be continuous through all penetrations
201
Tighter is better - any concerns?
204
© Building Science Press. Reprinted with permission.
Air barrier at fireplace
Chimney shafts and penetrations 205
Tub Air Sealing206
© Building Science Press. Reprinted with permission.
Prepare for the tub before the plumber arrives
207
208Provide rigid blocking
209
210Air-seal connections at house to garage
211
Plumbing, electrical & HVAC penetrations need attention
212
213Air Leakage at recessed light
214
Select the best method for your fixtures
215
Gaskets
Always choose airtight recessed lights for unconditioned spaces Gaskets
Air Flow Barrier-Exterior
■ A well detailed house wrap or weather barrier can also be an effective air barrier
■ It must connect to the foundation and the ceiling air barrier
■ Must be durable through the construction process
216
217
Air Sealing Summary
■ Reduce energy loss
■ 1/3 of htg/clg bill can be from air leakage
■ Reduce infiltration of harmful air
■ Garage connection
■ Improved comfort
■ Less drafts
■ Less noise & dust
219
Insulation Installation 220
Determine the thermal enclosure 221
Conditioned space
Rigid Air Barrier
Insulation essentials■ Most insulation types must
be combined with an air barrier...touching on all 6 sides
■ Insulation must be free of:
■ gaps
■ voids
■ compressions
222
223
224
IECC Climate Zones- U.S. lower 48
More Insulation - Minnesota 2015
■Higher R-value requirements for ceilings, walls, basements and crawl spaces (Table R402.1.1).
225
Insulation Ceiling R-value
Wood Frame R-value
Basement R-value
Crawlspace R-value
Climate Zone 2009 2015 2009 2015 2009 2015 2009 2015
6 38 4919,
13 + 5
20, 13 +
510 15 10 15
7 44 49 19 21 10 15 10 15
2” x 4” wall with various cavity and/or continuous insulation insulation
Total wall R-Value - including framing, insulation, sheetrock, OSB
etc...
R-13 cavity insulation ( batts - perfect install ) 10.17
R-13 Batt with R-5 cont. ext. insulation 15.17
R-13 blown cavity + R-10 cont. ext. insulation 20.17
Staggered Stud - 2 x 4 on 2 x 6 plates Completely filled with insulation R-24.5 16.6
What’s my R-Value?226
2” x 6” wall with various cavity and/or continuous insulation insulation
Total wall R-Value - including framing, insulation, sheetrock, OSB
etc...
R-19 cavity insulation ( batts - perfect install ) 14.42
R-19 Batt with R-5 cont. ext. insulation 19.42
R-21 blown cavity ( fiberglass etc.) 15.05
R-23.5 blown cavity ( HD fiberglass) 15.77
HD spray foam ( 2” + R-14 blown) a.k.a. flash and blow 16.58
R-21 blown cavity + R-5 cont. ext. insulation 20.05
R-21 blown cavity + R-10 cont. ext. insulation 25.05
What’s my R-Value?227
Insulated Sheathing will be normal 230
Framing for Insulation- Wall systems 234
■ Provide structural integrity, but insulate areas we sometimes miss.
235
Where 4 is good.... 236
5 is better....Graphics Courtesy of Building Science Corp.
9 or more has got to be enough! 237
238
239
Graphics Courtesy of Building Science Corp.
Delivery or Disposal?
240
Graphics Courtesy of Building Science Corp.
Simplified Framing
241
Carpentry Made Easy
William Bell,1858
A 3 stud corner 242
Diagram from CMHC Best Practices
Two-stud corner243
© Building Science Press. Reprinted with permission.
Interior wall junction 244
Ladder Blocking
245
© Building Science Press. Reprinted with permission.
In the field 246
247
Framing for Success
.......The Same
248
Insulating the Enclosure
■ All products have specific needs...
249
Insulation Must.... 251
Be installed properly:■ No compressions
■ No voids
■ Touching all 6 surfaces
■ Be properly mixed (foams)
■ Be compatible with other materials
■ Be combined with an air barrier or be one
■ Not be subjected to constant wetting cycles
Poor installation affects comfort, performance and durability 252
Compressions and voids reduce performance 254
255
256
257